Space is dangerous

There are lots of ways for things to go wrong off-Earth.

Prompted by some recent reading of Science Fiction stories old and new, our consultants have been pondering how dangerous Outer Space really is.  Of course there are the spectacular dangers that come from needing to go faster and farther than anything on Earth.  High-performance vehicles, especially experimental ones, always have the potential to explode or fall apart in catastrophic ways.  But our concern was with more subtle things and those that take more time to work.

Begin with the necessity to take our environment with us, in particular air and food, and get rid of wastes.  Humans are far from being closed systems.  In our Earthly habitat it takes a matter of square kilometers per person of other plants and animals to feed a human and clean up after one.  While the need can be compressed into a smaller and lighter package by using machines, it cannot be dispensed with.  It can also be limited by keeping to shorter voyages, but any significant penetration of the final frontier is going to mean trips of very long duration.  And while one may manage to stockpile years of supplies, a malfunction in the carbon-dioxide scrubbers out beyond Jupiter will be very serious indeed.

Then there’s radiation.  Outside of the Earth’s atmosphere and magnetosphere there are copious amounts of particles that are mostly of interest to high-energy physicists.  Introduced into the human body they can cause serious damage.  One can, of course, build shielding into the hull of one’s spaceship; but shielding is heavy, and protecting against the strongest solar storms would take quite a lot of it.  Even going to a small, cool, low-mass star doesn’t help, because they produce particularly strong flares of particles and radiation.

We have only begun to investigate things with longer-term effects.  So far we’ve found that even regular exercise doesn’t eliminate bone loss during extended periods of weightlessness.  And we know that lower doses of radiation over a long period can increase cancer risk, plus perhaps that of other chronic diseases.

So we think SF authors would be more realistic if they paid more attention to the dangers of space.

However, we haven’t quite come to the conclusion that spacefaring is closed to humans.  In part, our reasoning is by analogy, which is possibly the least rigorous of methods.  When the railroad was first introduced there were fears that moving at such a high rate of speed, above 20 or even 30 miles per hour, would make it impossible for people to breathe.  (In fact, the coal smoke from the boiler was more dangerous to respiration.)  And in a documentary on the opening of the Space Age, astronaut John Glen mentioned that there were fears that extended weightlessness would make it impossible for his eyes to focus, and so he’d be unable to read his instrument panel.  It didn’t turn out that way.  So maybe what we fear will turn out to be no barrier to Outer Space.

Perhaps through modifying humans.  It might be that we can reduce radiation-induced cancer through importing genes from the naked mole-rat, for instance.  Humans could indeed be a spacefaring race, just not humans like us.